{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T17:44:26Z","timestamp":1779299066050,"version":"3.51.4"},"reference-count":15,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,28]],"date-time":"2025-01-28T00:00:00Z","timestamp":1738022400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NICD operational funding"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>Background: Human central nervous system infections due to free-living nematodes, although extremely rare, are usually fatal. Immunodeficiency has not been a feature of most of these cases, unlike the situation pertaining to disseminated Strongyloides stercoralis infection. Case report: An elderly immunocompetent man presented with a history of tinnitus and otalgia, progressing to central nervous system involvement with confusion, weakness, and other neurological signs. Examination revealed a unilateral external auditory canal soft tissue mass and radiological evidence of ipsilateral temporal bone destruction and brain parenchymal disease. A biopsy of the ear canal mass revealed the presence of an unidentified nematode species, and treatment with anthelminthics was started. The patient\u2019s clinical condition deteriorated and he died shortly after admission to the intensive care unit. The immediate cause of death was bronchopneumonia. During the autopsy, an extensive involvement of the right middle cranial fossa was found, with destruction of the squamous and petrous parts of the temporal bone. Results: We identified adult, larval, and egg stages of a free-living nematode in the antemortem external auditory canal tissue mass and the post-mortem brain samples. Polymerase chain reaction assays, with Sanger and whole-genome sequencing, identified Cephalobus cubaensis. This is a free-living species not previously known to be pathogenic to humans, although nematodes of the same genus have caused mastitis in horses. Conclusions: Microscopic appearance and the invasive behaviour of the pathogen evoked a putative diagnosis of Halicephalobus gingivalis, the most frequently reported free-living nematode infecting humans. However, this nematode\u2019s size and anatomical features, and the clinical presentation and duration of illness, prompted the consideration of an alternative species. We speculate that an initial bacterial otitis externa provided the opportunity for colonization by the nematode from an environmental source and subsequent invasion.<\/jats:p>","DOI":"10.3390\/tropicalmed10020037","type":"journal-article","created":{"date-parts":[[2025,1,28]],"date-time":"2025-01-28T06:47:29Z","timestamp":1738046849000},"page":"37","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Central Nervous System Infection by Free-Living Nematode Cephalobus cubaensis in a Human Host in Africa"],"prefix":"10.3390","volume":"10","author":[{"given":"Charlotte","family":"Sriruttan-Nel","sequence":"first","affiliation":[{"name":"Parasitology Reference Laboratory, Centre for Zoonotic Emerging and Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg 2192, South Africa"},{"name":"School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chelline","family":"Cairns","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, Victoria Mxenge Hospital, Division of Internal Medicine, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Durban 4013, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shareen","family":"Boughan","sequence":"additional","affiliation":[{"name":"Parasitology Reference Laboratory, Centre for Zoonotic Emerging and Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg 2192, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bhavani","family":"Moodley","sequence":"additional","affiliation":[{"name":"Parasitology Reference Laboratory, Centre for Zoonotic Emerging and Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg 2192, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lisa Ming","family":"Sun","sequence":"additional","affiliation":[{"name":"Parasitology Reference Laboratory, Centre for Zoonotic Emerging and Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg 2192, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4933-8806","authenticated-orcid":false,"given":"Wai Yin","family":"Chan","sequence":"additional","affiliation":[{"name":"Sequencing Core Facility, National Institute for Communicable Diseases a Division of the National Health Laboratory Service, Johannesburg 2192, South Africa"},{"name":"Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria 0002, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4672-5915","authenticated-orcid":false,"given":"Arshad","family":"Ismail","sequence":"additional","affiliation":[{"name":"Sequencing Core Facility, National Institute for Communicable Diseases a Division of the National Health Laboratory Service, Johannesburg 2192, South Africa"},{"name":"Department of Biochemistry and Microbiology, Faculty of Science, Engineering and Agriculture, University of Venda, Thohoyandou 0950, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0895-5659","authenticated-orcid":false,"given":"Absalom","family":"Mwazha","sequence":"additional","affiliation":[{"name":"Department of Anatomical Pathology, National Health Laboratory Service, Durban 4001, South Africa"},{"name":"Discipline of Anatomical Pathology, Nelson R Mandela School of Medicine, School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban 4041, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9625-2573","authenticated-orcid":false,"given":"Praniel","family":"Bennimahadeo","sequence":"additional","affiliation":[{"name":"Department of Diagnostic Radiology, Victoria Mxenge Hospital, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Durban 4013, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nithendra","family":"Manickchund","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, Victoria Mxenge Hospital, Division of Internal Medicine, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Durban 4013, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mthabisi","family":"Moyo","sequence":"additional","affiliation":[{"name":"Ear, Nose and Throat Surgery Department, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Durban 4041, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thabani","family":"Nkwanyana","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Victoria Mxenge Hospital, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Durban 4013, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mpumelelo Z.","family":"Msimang","sequence":"additional","affiliation":[{"name":"Department of Anatomical Pathology, National Health Laboratory Service, Durban 4001, South Africa"},{"name":"Discipline of Anatomical Pathology, Nelson R Mandela School of Medicine, School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban 4041, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ahmed","family":"Essa","sequence":"additional","affiliation":[{"name":"Histopathology Division, Lancet Laboratories, Durban Branch, Johannesburg 2090, South 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